Alert archive / South Dakota / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 106, NWS Sioux Falls, SD

July 23, 1987Bon Homme County, Yankton County, South Dakota

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 23, 1987, 1:44 PM CDT for Bon Homme County, Yankton County, South Dakota. It was in force for 46 min.

The area

The counties it named.

The facts

Issued
Jul 23, 1987, 1:44 PM CDT (18:44 UTC)
Expired
Jul 23, 1987, 2:30 PM CDT
In force
46 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

Counties Bon Homme County, SD, Yankton County, SD

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 6.7 hours before the alert went out and 321 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 12:00Z on 1987-07-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 260 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, N. Platte/Lee Bi, NE at 12:00Z on 1987-07-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 91 square meters per square second.1939Sfc1 km3 km6 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
260 J/kg
Mixed-layer CIN
-517 J/kg
Mixed-layer LCL
1449 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
91 m²/s²
0-3 km storm-relative helicity
89 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 23, 12:20 PM CDTSevere Thunderstorm WarningFSDTodd55 min
Jul 23, 12:31 PM CDTSevere Thunderstorm WarningFSDGregory59 min
Jul 23, 1:02 PM CDTSevere Thunderstorm WarningFSDCharles Mix43 min
Jul 23, 1:54 PM CDTSevere Thunderstorm WarningFSDBon Homme, Charles Mix66 min
Jul 23, 6:39 PM CDTSevere Thunderstorm WarningFSDTodd66 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 1987Every severe thunderstorm warning in 1987

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive.